The present invention relates to an electromagnetic camshaft-adjuster device.
Such a device is generally known from the prior art and serves for the so-called reset sensing, wherein for example an induction signal that is sensed and evaluated in the non-energised state of the coil unit of the armature unit moving in accordance with the camshaft position is evaluated at the connecting terminals of the coil unit. Such a device is shown for example by DE 10 2006 035 225 A1 of the applicant.
In addition to this, there are further possibilities of monitoring a correct functioning of a camshaft adjustment, wherein this, however, also takes place indirectly in that for example such a camshaft adjustment monitoring is combined with an anti-knock sensor electronic that is present anyhow, or however a crankshaft acceleration is sensed and evaluated.
All these procedures have in common, however, that any malfunctioning is difficult to determine out of the respective signal and, accordingly, a very complicated (and potentially unreliable) electronic signal evaluation is necessary for determining the concrete tappet position (adjusting unit) for the camshaft. Added to this is that with the induction technology utilised as being generic only a movement of the tappet or of the armature unit can be determined due to the principle, but not its/their stationary state position; in particular, it is not possible with means of the evaluation of an induction coil voltage to reliably sense a (standing) end position of the tappet (adjusting unit) engaging in the camshaft.
As a further potential technical problem it happens that the induction voltage measured in the generic manner is dependent on factors such as movement velocity (this is in turn dependent on the engine rotational speed), the current ambient temperature, contaminations etc., so that thus a desired secure detection of incorrect switching operations is not guaranteed in any operating state.
It is therefore the object of the present invention to create a simple, reliable camshaft-adjuster device that can be realised with a minor effort in terms of manufacturing and evaluation, with which a current camshaft adjusting state or a current position of an armature brining about the camshaft adjustment including the adjusting unit driven by said armature can be reliably determined.